2.9 Iowa Product-Specific Use Restrictions

2.9 Iowa Product-Specific Use Restrictions

Quick Answer: Iowa layers state restrictions on top of the federal label. Every atrazine product is a state restricted-use pesticide limited to certified applicators, capped at 3 lb actual active ingredient per acre per calendar year statewide and 1.5 lb/A/yr in designated pesticide management areas, with a 50-foot application setback and a 100-foot mixing and loading setback from wells, cisterns, sinkholes, streambeds, lakes, and impoundments. High volatile ester formulations of 2,4-D and 2,4,5-T are banned outright in five county areas. Iowa may add restrictions like these, but it can never relax a federal restricted-use classification.

How Iowa Classifies Restricted-Use Pesticides

IAC 21—45.30 does two things. First, it adopts by reference every product EPA classifies as restricted use under FIFRA and 40 CFR 152.164(c). Second, it recognizes products the department classifies as restricted use. The result is a floor-and-ceiling structure: the federal list is the floor, and Iowa can add to it but never subtract from it. A product that is general use on its federal label can be restricted use in Iowa; the reverse is impossible.

The practical consequence is that a national study manual or a product's federal classification is not a reliable answer to "who may buy this in Iowa."

Atrazine: Iowa's Signature State Restriction

Atrazine — chemically 2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine — is the flagship example. IAC 21—45.51 classifies every pesticide containing atrazine, or any combination of active ingredients including atrazine, as a restricted use pesticide for distribution, sale, or use in Iowa. All atrazine products are restricted for retail sale to, and use by, certified applicators only.

Dealers selling atrazine must also file an annual report listing the full trade name, EPA registration number, and total volume in gallons or pounds sold, filed with the annual sales report required by IAC 21—45.47.

The Rate Caps

Both caps are expressed as actual active ingredient, not product, and both run on a calendar year, not a crop year. Where a product label sets a lower maximum, the label controls — the state cap is a ceiling, not a permission.

The pesticide management areas are groundwater-sensitive parts of the state. They cover all of Allamakee, Clayton, Dubuque, Floyd, Humboldt, Jackson, and Winneshiek counties, plus named townships in Black Hawk, Bremer, Butler, Cerro Gordo, Chickasaw, Clinton, Delaware, Fayette, Howard, Jones, Kossuth, Linn, Mitchell, Pocahontas, and Worth counties. The geography is not accidental: it tracks Iowa's karst and shallow-bedrock country in the northeast, where surface water reaches aquifers with almost no filtration.

The Atrazine Setbacks

• Application setback — 50 feet. No atrazine-containing substance may be applied within 50 feet of a sinkhole (measured from the outer edge of slope), well, cistern, lake, water impoundment, or similar area. The rule names abandoned wells, agricultural drainage wells, drainage well surface inlets, and drinking water wells explicitly.
• Mixing and loading setback — 100 feet. Atrazine may not be mixed, loaded, or repackaged within 100 feet of any well, cistern, sinkhole, streambed, lake, impoundment, or similar area unless it is handled in the original unopened container, or unless the site meets the secondary containment requirements of IAC 21—44.
• Cleanout. Mixing, loading, and equipment cleanout must either meet the IAC 21—44 secondary containment standard or be done in the field of application. Equipment and container wash waters go to labeled use areas or become dilution makeup water applied to labeled use areas.

The 50/100 split is a favorite exam item: the tighter number applies to the higher-concentration activity. Handling concentrate near a well is riskier than spraying dilute solution near one.

High Volatile Esters of 2,4-D and 2,4,5-T

IAC 21—45.27 bans high volatile ester formulations of 2,4-D and 2,4,5-T — those whose alcohol fraction contains five or fewer carbons — in Harrison, Mills, Lee, and Muscatine counties, and in the part of Pottawattamie county west of Range 41 West of the 5th P.M.

The rationale is vapor drift. Short-chain (high volatile) esters vaporize readily after the spray dries and move to sensitive crops — grapes, tomatoes, and other broadleaf specialty crops concentrated in those river-valley counties. Low volatile esters and amine formulations remain available. When a question describes a grower in western Pottawattamie or along the Mississippi asking about an ester 2,4-D, the county is the point of the question.

Hazardous Rodenticides and Other Named Products

Chapter 45 restricts several specific products by name, and the pattern is worth knowing even where the details are narrow:

• Sodium fluoroacetate (1080), thallium sulfate, and strychnine are subject to IAC 21—45.20 controls before distribution. Iowa separately prohibits selling or possessing thallium or thallium compounds for pest control under 21—45.23.
• DDT and DDD may be distributed, sold, or used only for pests of public health importance and quarantine pests, under the direct supervision of public health or quarantine officials (21—45.32).
• Heptachlor and lindane carry their own distribution and use restrictions (21—45.34, 21—45.35).
• Inorganic arsenic use requires a two-stage approval process through the department (21—45.33, 21—45.37).
• A noncertified applicator may never use a restricted-use pesticide containing sodium cyanide or sodium fluoroacetate, and 40 CFR 171.103(c)(7) requires additional certification for those products, for fumigants, and for aerial application.

The Rule Behind the Rules

Every one of these state restrictions exists because Iowa concluded the federal label was not protective enough for Iowa conditions — shallow aquifers, karst geology, and specialty crops in defined counties. That is exactly what a state running an EPA-approved certification plan is allowed to do. It is also why an applicator who studies only a national core manual will miss these questions: nothing in the federal material mentions Winneshiek County or Range 41 West.